Identification and determination of fenitrothion photolysis products in water—methanol by gas chromatography—mass spectrometry

167

Analytrca Chumca Acta, 262 (1992) 167-178

Elsevler Science Publishers B V , Amsterdam

Identification and determination of fenitrothion photolysis products in water-methanol by gas chromatography-mass spectrometry ~1 G Durand Envrronmental Chemutry

Lkpartment,CID-CSIC, c / Jordl Guona, 18-26, 08034 Barcelona &am)

M Mansour Instttut fir Okologixhe Chemre, Schulstrasse 10, W-8050 Frerrmg-Attaching (Germany)

D Barceld * Enuuonmental Chenustry Department, CID-CSK,

c /Jordr Gzrona, 18-26,08034,

Barcelona (@am)

(Received 16th September 1991, revised manuscript received 8th January 1992)

Abstract

The photodegradatlon of femtrothlon was exammed m dlstdled water contauung methanol After 7 h of W Irradiation urlth a high-pressure mercury lamp, a fractlonatlon step was carried out on a senu-preparative sd~ca gel column Eighty-eight fractions were collected by increasing the polanty of an eluent mmture of n-hexane-ethyl acetate (95 + 5) up to 100% ethyl acetate Three more polar fractions m eluent nuxtures of n-hexane-acetone (50 + 501, pure acetone and acetone-methanol (25 + 75) were obtamed The breakdown products formed were ldentlfled by gas chromatography-mass spectrometly wth electron Impact (EI) lonlzatlon An estunate of the amount of femtrothlon degraded mdlcated that after 7 h of madlatlon, 10% of the parent compound still remamed and different oxldatlon, lsomeruatlon and solvolysrs products were produced The P = S group was oxldlzed to gwe femtrooxon and trunethyl phosphate m amounts of 0 1% and 3%, respectwely Carbomethoxyfemtrothlon, due to oxldatlon followed by solvolysis, and the lsomeruatlon products O,O,S-tnmethyl phosphorothloate and the S-methyl Isomer of femtrothlon were obtained as photoalteratron products at lo%, 10% and 3%, respectively Other compounds corresponded to demtrofemtrothlon, carbomethoxydemtrofemtrothlon, parathion-methyl and Cmtro-mcresol at 0 2%, 0 4%, 0 4% and 0 4%, respectively The El mass spectra and the structures of the Ions of the dtierent femtrothlon photolysls products are gwen Keywords

Gas chromatography, Mass spectromeq,

Femtrothlon, Pestlcldes, Photolysls

Organophosphorus pestlcldes are used as msectlcldes m animal husbandry and in many agncultural apphcatlons for crop protection and/or ehmmation of ectoparasites As a consequence of their widespread use, residue levels varymg from ’ Presented at the 3rd Workshop on Chenustry and Fate of Modem Pestlades, Bdthoven, Netherlands, 4-6 September 1991

a few ng 1-l up to 10 pg I-’ m water and from 10 ng g-’ up to 1000 ng g-’ in sod samples have been detected [l-41 After apphcatlon, their em+ ronmental fate IS poorly understood but several degradation pathways such as hydrolysis, photolySISand mlcroblal transformation may be possible Photolysls IS one of the major transformation processes affecting the fate of pestlcldes m the aquatic environment Three mam hght sources

C003-2670/92/.$05 00 0 1992 - Elsevler Science Pubhshers B V All rights reserved

168

are used for Its mvestlgatlon natural summer sunlight, the suntest apparatus and mercury lamps It has been demonstrated that the use of different light sources under identical aqueous conditions produces similar degradation products, the only difference bemg the kmetlcs of formation [5,61 As there 1s a need for ldentlfymg the many photodegradatlon products obtained, large amounts of the parent pesticide need to be photonradiated Because many chemicals do not exhlblt good solublhty m water, it 1s essential to use photochemically inert organic solvents, such as acetomtnle or methanol [6-91 Studies have also been done m pure organic solvents such as benzene [5] or oxygenated hexane [lo] The lrradlatlon tnne 1s also very variable dependent on the kmetlcs of degradation of the compound of mterest, and may vary from 3 up to 72 h [5,91 Numerous studies on the photochemical transformatlons of a vanety of organophosphorus pesticides, e g , parathion-ethyl and -methyl, dlazlnon, lodofenphos, fenthlon, methldatlon, chlorpynfos, chlormephos and femtrothlon, m solution and on plant and leaf surfaces, have been reported [5,10-171 It 1s known that the phosphorothlonate (P = S) pesticides, such as parathion and femtrothlon, are converted into then oxygen analogues, oxon (P = 01, by photolysls [5,1012,141 These 0x0 metabohtes are of concern because they are the activated forms of the organophosphorus pestlccldes, with a considerably stronger mhibltlon of cholmesterase actlvlty than that exhlblted by the parent compounds 1181 The S-methyl Isomers, which also exhibit a very dlfferent blologlcal actlvlty than their O-alkyl precursors [18], are produced by thermally Induced isomenzatlon, thus takmg place during synthesis and storage, and by photolysls [191 After photodegradation expernnents have been completed, lsolatlon of the reaction products 1s reqmred with further ldentlficatlon by gas chromatography-mass spectrometry (GC-MS) One of the mam problems m the ldentlflcatlon of the photoproducts IS that most of them are not commeraally avadable and confirmation by synthesis 1s not common practice For this reason, the ldentlficatlon of the different photoproducts offered often some dlscuss1on, as pomted out in a

G Durand et al /Anal Chum Acta 262 (1992) 167-178

recent paper on the fragmentation of substituted phenyl phosphorothloates [19], where It was shown that some of the data published on the ldentlflcatlon of photoproducts of lodofenphos [16] and fenthlon [5] appeared to be Incorrect after a careful exammatlon of the different fragment ions, e g , fenthlon oxon cannot exhibit a promment m/z 125 ion, which 1s a typical behavlour of the fenthlon functional group Llquld chromatography (LC)-thermospray MS was also shown to be a valuable technique for the ldentlflcation of oxygen analogues of organophosphates and acldlc metabohtes [20-221 Although a partly qualitative ldentlflcatlon by GC-MS of some photodegradation products of femtrothlon has been reported [lO,ll], no other papers have appeared that either confirm prevlous obtamed results or identify new photolysls products In addition, incorrect assignments have recently been detected m the ldentlficatlon of different phosphorothloates by GC-MS [19] For the aforementioned reasons, and consldermg that a quantltatlve study of the photolysls products formed had not prewously been undertaken, It was considered of mterest to make a systematic mvestlgatlon of such an ldentlflcatlon of the photodegradation products of femtrothlon and to compare then fragmentation schemes with the GC-MS behavlour of organophosphorus pestlcldes In addition, the deternunatlon of the dlfferent photodegradation products formed would be of help m evaluating the main photodegradatlon processes of femtrothlon m water-methanol This paper presents quahtatlve and quantltatlve results on the photodegradation of femtrothIon m water-methanol After UV Irradiation and lsolatron of the different fractions, ldentlflcatlon was made by GC-MS with electron Impact (EI) lonlzatlon In this way, ldentlficatlon of the dlfferent metabohtes will be feasible by comparing their spectra with authentic standards, when avadable, with library searches and with prevlously published data on GC-MS photolysls products of femtrothron and other phosphorothloates exhibiting a common fragmentation behavlour [5,10,11,19,23-261 Some of the metabohtes formed are reported here for the first tune and/or are common to other phosphorothloate pestl-

G Durand et al /Anal

Chun Acta 262 (1992) 167-178

169

I

12

12

14

14

16

TIM

T!h~~

16rcr’LF!

22

24

26

20

22

24

26

26

Fig 1 GC-MS traces of the different (A) aqueous and (B, D, E, G) n-hexane-dlchloromethane extracts after fractlonatlon with the semi-preparatwe sdlca gel column and combmatlon of the extracts with slmdar K-W traces

170

crdes, e g , parathion-methyl This work 1s a continuation of previous work concerning the rdentrfication of pesticide photolysls products m water by various chromatographrc techniques [6,17,22]

G Durand et al /Anal Cham Acta 262 (1992) 167-178 TABLE 1 Eluent mixture and fractions collected m silica gel serm-preparatlve column after lrradlatlon of femtrothlon m water Elution volume (ml)

Eluent n-Hexane (%)

Ethyl acetate (o/o)

95 90 90 85 85 80 70 60 50 40 30 2Q 10 0

5 10 10 15 15 20 30 40 50 60 70 80 90 100

n-Hexane (%I

Acetone (%o)

50 0

50 100

Acetone (%I

Methanol (%)

EXPERIMENTAL

Chemxals

Femtrothron (99 7%) and femtrooxon, analytlCal-reagent grade standards, were gifts from Sumrtomo Chemrcal Co (Osaka) and parathron-methyl was purchased from Promochem (Wesel) Pesticide-grade ethyl acetate, acetone, methanol and n-hexane and s&a gel were obtained from Merck (Darmstadt) Photoiysls expenments

Femtrothron showed slow photodegradatron m drstrlled water containing 2-4% of methanol when using the suntest apparatus and without the use of acetone as photosensmzer [17] As a consequence, m order to identify the possible photodegradatton products, femtrothron solutron was irradiated with radiation from a hrgher intensity light source (HPK 125 W high-pressure mercury lamp) which was passed through a quartz filter, which also increases degradation [6] As femtrothron has a limited solubihty m water (14 mg 1-l) and the purpose of this work was to identify as many metabohtes as possible, water-methanol solutions were employed Therefore, 100 mg of femtrothron were drssolved m 600 ml of watermethanol (5 + 1) and was kept m a l-l round-bottomed Pyrex flask, attached to a high-pressure mercury lamp In order to ehmmate any effects from the heat which the mercury lamp emrtted, the vessel was cooled wrth crrculatmg distilled water provided by a coohng machme The temperature of the test solution was kept at 15°C m a water-bath After 7 h of nradratron, the femtrothron solutron was extracted with 150 ml each of dlchloromethane, n-hexane and drchloromethane The aqueous solution that remained was evaporated to dryness and the residue was drssolved m 0 5 ml of ethyl acetate This total latter extract 1s called the aqueous extract m the Results and Drscussron section The drchlorometh-

500 500

500 500 500 500 500 500 500 500 500 500 500 500

200 200

150

25

75

Fraction No

1-13 14-19 20-23 24-29 30-34 35-40 41-45 46-50 51-56 57-63 64-68 69-74 75-79 80-85

86 87

88

ane-hexane extracted solutron was loaded on a semi-preparative srhca gel column (52 x 15 cm I d 1, prepared m the laboratory, from whtch 88 fractions were obtained A small plug of glasswool and sand was placed m the column followed by a dry packmg of silica gel After connecting the vacuum, n-hexane was introduced mto the column The 88 fractions collected and the eluent mrxtures used are indicated m Table 1 After the fractronatron was completed, the different fractions were analysed by LC with UV detection at 254 nm The extract fractions that were found to be mrxtures of the same compounds were combined and the solvent was removed The combined fractions are indicated m Table 1 The residues were dissolved m 250 ~1 of ethyl acetate and were directly injected mto the GC-MS system usmg the experimental conditrons descrrbed above Figure 1 shows the GC-MS traces of the

6

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8 8Es

9

Cl1

16

(3

765

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158

EBB

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mtn)

n,n>

of the different

IW

S¶6

Fig 2 El mass spectra

t .

l

km

ldentlfied

260

m the GC-MS

300

f

1

3.8E6j

ilWW I

traces III Fig

Al

kan

Ssm

I

‘/’

5cmr1

A

(28.047

L

321

(21.174

I

(22

?

I

2S

phorotktols

1241

1717

I

1219

mtn)

rlnl

RIB)

atId.

I

263

I

tu+hyl

/

B2c=

O-_(4-

277

Bl

2.77

2Bee

4eee

69

I i

/ 263 1

0.0. d

I

t

Fig 2 (contmued)

SCU,

+7668

878

m(n)

h :36

3_uthyl-4-nl+ro-

eae

IlutYChrrnm

c15.794

Phrnol.

lee

* 388

CSCX>

AL

2,77 c

B4

G Durand et al /Anal Chm Acta 262 (1992) X67-178

5

tm

173

G htrand et al /Anal Chun Acta 262 (1992) 167-178

174

(A) aqueous and (B, D, E, G) n-hexane-dlchloromethane extracts Figure 2 shows the EI mass spectra of all the different compounds identified m the GC-MS traces m Fig 1

sample Femtrooxon and parathion-methyl were determined with the pure standards

RESULTS

GC-MS deterrnmatrom A 30 m x 0 25 mm 1 d fused-sdlca capillary

column coated with chemically bonded phenylcyanopropylmethyl DB 1701 (J L&W &lent&, Folsom, CA) was programmed from 90 to 280°C at 6“C/mm The mjectlon volume was 2 ~1 and the sphtless mjectlon mode was used A Hewlett-Packard (Palo Alto, CA) Model 5995 instrument interfaced to a Model 59970C data system was used for GC-El-MS The same fused-slhca column as described above was used and directly introduced mto the ion source Hehum was used as the carrier gas at 30 cm s-l The ion source and the analyser were held at 200 and 23O”C, respectively EI mass spectra were obtained at 70 eV The different compounds identified m the GC-MS traces were determined by selected ion momtormg (SIM) using femtrothlon as a standard

AND DISCUSSION

In Fig 3 the tentative photodegradation scheme of femtrothlon (B3) m water with the labels of the different photoalteratlon products identified 1s shown In Table 2 the fraction number, characterlstlc ions with their relative abundances, labels and retention times m the GC-MS traces of the different compounds indicated m Figs 2 and 3 are shown Figure 4 shows the characterlstlc ions of the mam fragments reported m Table 2 The different photoalteratlons products identified are discussed below Aqueous extract of lrradrated ferutrothlon soiutlon

The EI mass spectra of the different photoproducts identified were assigned to compounds with molecular weights of 140 (Al), 156 (A2) and 234 (A3), respectively These photolysls products

TABLE 2 Photoalterat,on

products

of femtrothlon

m dlstdled water

contammg methanol after 7 h of UV lrradlatlon wdh a high-pressure

mercury lamp

m/z (relative

Fraction No Aqueous Aqueous

extract extract

Aqueous

extract

2-12 2-12 2-12 2-12 37-42 37-42 48-51 88

79 (30),95 (20), 110 (loo), 140 (15) 79 (55),95 (lo), 110 (loo), 126 (201,156 (55) 79 (201,109 (SO), 126 (601, 173 (801,204 (lOOk 234 (25) 63 (lo), 79 (15), 93 (3O),lC@ (loo), 125 (551,245 (30), 276 (100) 79 (25),93 (151, 109 (loo), 125 (lOO), 263 (70) 63 (15),79 (251, 93 (15), 109 (70h 125 (lOOI, (50), 277 (100) 79 (lo), 125 (lOO), 260 (501,277 (2@ 77 (40), 136 (loo), 153 (50) 77 (lo), 105 (401, 109 (lOOI, 125 (151,232 (100) 79 (15), 109 (loo), 244 (loo), 261(20) 63 (lo), 79 (20), 109 (60), 125 (1001, 181(15), 290 (lo), 321(70)

Retention trme m GC-MS (mm)

Label

Amount formed (%)

Al A2

3 10

30 57

A3

3

117

Bl

04

20 8

B2

04

21 1

mtenslty, o/o)

B3

10

22 3

B4 Dl D2

3 04 02

24 6 15 8 179

El Gl

01 10

212 260

G Durand et al /Anal Chun Acta 262 (1992) 167-178

were ldentlfled as trimethyl phosphate (Al), O,O,S-trimethyl phosphorothloate (A21 and tetramethyl pyrophosphate (A3) The spectrum of trimethyl phosphate matches the previous data on this compound 1261and the EI mass spectra of all three compounds, Al, A2 and A3, match those of the three mam photolysls products of parathion-methyl [5] The EI mass spectra of Al and A2 reported m the literature were matched with authentic standards The formation of ldentlcal photoproducts for femtrothlon and parathlon-methyl 1s explained by the fact that they have the same functional group structure and consequently the photoproducts formed from such a structure are identical With parathion-methyl the A2/Al formation ratio was ca 3 [5], as for femtrothlon (see Table 21, although the absolute amount formed was lower as a fluorescent emlsslon lamp having its maximum spectral emlsslon at 360 nm was employed [5] The spectra and the structures of the most slgmflcant ions are reported in Figs 2 and 4, respectively In Fig 4 it should be noted that the m/z value of 126 m A2 corresponds to [(CH,O),PSH]+ whereas for A3 it corresponds to [(CH,O),P(O)OH]+ For the formation of compounds Al, A2 and A3 two molecules of femtrothlon are needed m a slmllar mechanism to that reported for the photolysls of parathlonethyl [S] or parathion-methyl 151,indicating that the third ethyl or methyl, respectively, does not arise from the solvent or the analytical protocol used This has been confirmed by the production of these metabolrtes by dlssolvmg the organophosphorus pesticides either m aqueous tetrahydrofuran, aqueous ethanol [S] or benzene [51and carrying out the photolysls experiments It should be mentioned that these photolysls products of femtrothlon were not identified m previous photolysls experiments on femtrothlon [lO,ll] Fractrons2-12 Compound Bl was identified as carbomethoxydemtrofemtrothlon and its spectrum and structure are shown m Figs 2 and 3, respectively Although this compound was not reported to be formed m previous studies on the photolysls of femtrothlon [ lo,1 11, its precursor, carbomethoxy-

175

femtrothlon, was observed m the same expenments The presence of Ions at m/z 63, 79, 93, 109 and 125 Indicates that the phosphorothloate moiety 1s present [19,23-251 (Fig 4) The ion at m/z 109 1s enhanced m comparison with the usual phosphorothloate pesticides e g , femtrothion, this can be attributed to the fact that there 1s a COOCH, group m the mera position that can more easily enhance the m/z 109 rearrangement ion as compared mth a CH, substltuent (as for femtrothlon B3) A second abundant ion at m/z 245 1s attributed to a loss of OCH, Compound B2 was identified by a library search as O,O-dlmethyl O-(-4 mtrophenyl)phosphorothloate, better known as parathion-methyl, with a molecular weight of 263 The other ions formed correspond to typical diagnostic ions of the phosphorothlonate moiety The Ions at m/z 109 and 125 are relevant due to the p-NO, substltutent which 1s a typical behavlour of phosphorothloate pesticides with para substltuents, as o&o-substituted analogues show a very low abundance of m/z 109 and 125 Ions 1191 The ldentlflcatlon of parathion-methyl was cheked by co-elutlon with an authentic standard, matching previous data [23,24] Although the formation of parathion-methyl from femtrothlon by UV Irradlatlon has not previously been reported [lO,lll, it has been pointed out that after UV irradiation dealkylatlon with loss of CH, occurs for phosphorothloate pestmdes, such as fenthlon [5] Compound B3 was identified as femtrothlon with a molecular weight of 277, with a loss of OH at m/z 260 that corresponds to the typical structure indicated m Fig 2, as reported elsewhere [10,11,26] From the two structures correspondmg to m/z 260 the femtrothlon fragment corresponds to that containing (CH,O),P(S)O This intense peak has been attributed to the hydrogen bonding between the methyl and the mtro groups and it 1s thought to be due to the loss of OH by a McLafferty rearrangement mvolvmg proton abstraction by an oxygen of the mtro group mdlcatmg the presence of a CH, group adjacent to an NO, group [3,10,11,23-261 Characterlstlc ions of the phosphorothloate group are also obtained Some differences were observed m the relative abundances of higher ions m the EI mass spec-

176

G Durand et al /Anal

+ii N

I

I

2

,T I 9

I

I

I

Chm Acta 262 (1992) 167-178

G Dun& et al /Anal ChumActa 262 (1992) 167-178

trum compared with prevrous results, thus leadmg to higher relative abundances when using the present mass spectrometer This 1s attributed to known drfferences when using dtfferent mass spectrometers [4,10,11,19] Compound B4 was ldentlfied as the S-methyl Isomer of femtrothron, as mdrcated by drfferent results First, its spectrum has common features wrth that of ferutrothron, with tons at m/z 125 (more abundant) and 260, the structures of which are Indicated m Fig 4 It should be noted that both structures exhibited (CH,SXCH,O)P(O) functronal groups, which correspond to the same molecular weight as femtrothron structures [10,11,19] Second, the mam drfference corresponds to the absence of an m/z 109 ion, which cannot be formed for thus compound as the (CH,Ol,P(O) structure does not exrst Finally, the S-methyl isomer of femtrothron exhrbrts a longer retention trme than femtrothron (24 6 versus 22 3 mm) All the assumptrons made here concernmg the rdentrftcatron of the S-methyl rsomer comcrde with results reported elsewhere on the photodegradatron of femtrothron [lO,ll] and also support the hypothesis of the formatron of S-methyl rsomers of other phosphorothroate pestrades, e g , parathton-methyl, by UV light C51 Fractwns 37-42 Compound Dl was rdentrfred as 3-methyl-4 mtrophenol by a library search and rt has been prevrously rdenttfred as one of the photolysrs products of femtrothron [lO,ll] Thus compound grves a EI mass spectrum wrth charactertstrc ions of m/z 153 and 136 The spectra and structures of the ions are grven m Figs 2 and 4, respectively Compound D2 was tentatively rdentrfred as demtrofemtrothron with a molecular wetght of 232 and Its structure 1s indicated m Frg 3 As reported prevrously [lo], demtrofemtrothton 1s hkely to be formed, and its EI mass spectrum exhibits a much lower abundance of m/z 125 than for other ions at m/z 232,109 and 105 The ions formed match previous results wrth even the for-matron of the Ion at m/z 105 which had a relative abundance of 64% [lo] The less abundant ion at m/z 125 IS due to the loss of the NO, group [ 101,leaving only the CH 3 meta-substrtuent

177

m the fenrtrothron structure The m/z 125 ion exhrbtts a lower relative abundance than m compound Bl (carbomethoxydemtrofemtrothron) Chvmg to an energetically favourable fragmentatron pathway, the COOCH, group of carbomethoxydemtrofemtrothron (spectrum Bl) can more easrly stabrllze the m/z 125 Ion as compared wtth the CH, group of demtrofemtrothron

k-4 Fractwns 48-51 Femtrooxon was Identified m EI This was supported by co-elutron with an authentic standard, by the typical features of the EI mass spectrum and by Its shorter retention time than femtrothron The EI mass spectrum 1s charactertzed by ions at m/z 79 and 109 with no formation of an ton at m/z 125, as no S 1s present m the molecule Also, a srgmfrcant amount of an ion with m/z 244 1s formed correspondmg to a loss of OH with a srmrlar explanatron as for femtrothion (see spectrum B3) [10,11,26] Fractwn 88 The compound was tentatrvely identified as carbomethoxyfemtrothron m Gl It IS hkely to be formed and its EI mass spectrum has been reported elsewhere [lo] In addition to the typical ions common to the phosphorothroate motety, three characterrstrc ions of carbomethoxyfemtrothlon corresponding to m/z 151, 181 and 321 were obtamed and match prevrous results reported for thus compound [lo] A second abundant fragment at m/z 290 was attributed to a loss of CH,O from the molecule with a tentative structure as mdrcateb m Fig 4 The formatron of this ion at m/z 290,ls srmrlar to the formatton of that at m/z 245 m Bl Hence we are rnclmed to believe that both compounds are sutular The spectrum of Bl 1s assigned to carbomethoxydemtrofemtrothron whereas rt 1s beheved that m thus instance Gl corresponds to carbomethoxyfemtrothron Conclusions This work has expanded the list of photolysrs products observed for femtrothron obtained m prevrous photodegradatron studies m aqueous so-

178

lutlons In addition, the data presented provide an estimate of the amount of each photoalteratron product formed after 7 h of UV lrradlatlon of femtrothlon dissolved m water-methanol (5 + 1) It 1s clear, that the combined use of an extenswe fractlonatlon step followed by GC-MS characterlzatlon offers a practical means of characterlzmg the complex mtiure of different photolysls products It was confirmed that oxldatlon was the major photolytlc decomposltlon route for femtrothlon m water-methanol (5 + I), but solvolysls and lsomerlzatlon should also be taken mto conslderation As 1s generally true m photolysls studies, other alteration products were observed m the GC-MS traces of the different fractions collected durmg the u-radiation studies, with a value of ca 60% However, owmg to the limited avallablhty of standards and dtilcultles of interpretation, none of these could be positively identified Thus, of the large number of compounds detected, only those listed m Table 2 were characterized Further research 1s needed by syntheslzmg other photoalteratlon products of femtrothlon tentatively identified and/or confirming the umdentlfred photoproducts In this latter instance the use of other MS techniques, e g , LC-thermospray MS, GC-high-resolution MS and GC-MSMS, wdl be of great help G Durand 1s the recipient of fellowship from the Fundacid Calxa de Pensions (Barcelona, Spain) and from the BMFT Spanish-German cooperation programme R Alonso 1s thanked for technical assistance This work was fmanclally supported by the Funda& Caura de Pensions

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